Radiant defrost panel for refrigerator



July 23, 1968 A. J. KOCH RADIANT DEFROST PANEL FOR REFRIGERATOR Filed Oct. 17, 1966 l @Iz/71 @law JKOC/zf,

United States Patent O 3,393,530 RADIANT DEFRGST PANEL FOR REFRIGERATOR Alan J. Koch, Evansville, Ind., assignor to Whirlpool Corporation, a corporation of Delaware Filed Oct. 17, 1966, Ser. No. 587,317 12 Claims. (Cl. 62-275) ABSTRACT F THE DISCLOSURE A frost-free, forced air flow refrigeration apparatus wherein moist air from an above freezing compartment of the apparatus is flowed in drying association with a drying means prior to the delivery thereof into chilling association with the evaporator. A defrost heater is provided comprising a partition defining an inlet chamber portion through which the return air is delivered prior to its delivery to the evaporator. The partition defines a horizontal wall with the air inlet being arranged to deliver air from the refrigerator compartments to above the wall with the evaporator being disposed below the wall. The heater wall is removably supported in the apparatus.

This invention relates to refrigeration apparatus and in particular to frost-free, forced air ow refrigeration apparatus.

In one conventional form of refrigeration apparatus, air is chilled by being passed in heat transfer association with an evaporator and then delivered to one or more compart-ments to be refrigerated. After passing through the compartments, the air is again passed in heat transfer association with the evaporator for recirculation to the compartments. In such refrigeration apparatus, moisture in the air tends to collect on the coldest surfaces of the system which are the surfaces associated with the evaporator and the surrounding walls rather than in the compartments to be refrigerated. Such a system is conventionally referred to as a frost-free refrigeration system.

In such a system, it is necessary from time to time to remove the collected frost. The present invention is concerned With an improved means for facilitating the frostfree operation and the defrosting of the apparatus.

Thus, a principal feature of the present invention is the provision of a new and improved refrigeration apparatus.

Another feature of the invention is the provision of such a refrigeration apparatus having new and improved means for facilitating the frost-free operation thereof.

A further feature of the invention is the provision of such a refrigeration apparatus having new and improved means for effecting defrosting of the portions of the apparatus lwhereon frost is caused to collect.

Still another lfeature of the invention is the provision of such a refrigeration apparatus having new and irnproved means for drying the air prior to the delivery to the evaporator.

A yet further feature of the invention is the provision of such a refrigeration apparatus having new and improved means for providing defrost heat defining a partition means for directing the air flow in a new and improved manner for facilitated frost-free operation and defrosting.

Another feature of the invention is the provision of such a refrigeration apparatus wherein means are provided for conducting relatively moist air from an-above freezing compartment in drying association with a drying means prior to the delivery of the air to the evaporator.

A yet further feature of the invention is the provision of such a refrigeration apparatus having a new and improved defrost heater comprising a partition means de- ICC fining an inlet chamber portion through which the return air is delivered prior to delivery to the evaporator.

Another feature of the invention is the provision of such a refrigeration apparatus wherein the inlet chamber portion is divided into two sections with the relatively moist air. from an above freezing compartment being returned through one section and the air from a below freezing compartment being returned through the other section, the air drying means being provided in the first section for drying the relatively moist air prior to the delivery thereof to the evaporator.

A further feature of the invention is the provision of such a refrigeration apparatus wherein the heater means defines a horizontal wall and the air inlet is arranged to deliver the air from the compartments to above the Wall, the evaporator being disposed below the wall.

Another feature of the invention is the provision of such a refrigeration apparatus including means for removably supporting the heater wall means in the refrigeration apparatus.

Other features and advantages of the invention will be apparent from the following description taken in connection Iwith the accompanying drawings wherein:

FIGURE 1 is a schematic front elevation of a refrigeration apparatus embodying the invention;

FIGURE 2 is a fragmentary vertical section of the refrigeration apparatus taken substantially along the line 2-2 of FIGURE 3;

FIGURE 3 is a horizontal section thereof taken substantially along the line 3 3 of FIGURE 2;

FIGURE 4 is a fragmentary vertical section thereof taken substantially along the line 4-4 of FIGURE 3; and

FIGURE 5 is an exploded perspective view of a portion of the refrigeration apparatus embodying the invention.

In the exemplary embodiment of the invention as disclosed in the drawing, a refrigeration apparatus generally designated 10 is shown to comprise a cabinet 11 defining an upper, above freezing, fresh food compartment 12 and a lower, below freezing, freezer compartment 13. The cabinet 11 further defines a lowermost apparatus space 14 in which is provided a compressor 15, a condenser 16, an evaporator 17, an air translating device 18, and a header tube 19, as best seen in FIGURES 3 and 4. The header tube or liquid refrigerant accumulator is placed in the refrigeration system between evaporator 17 and compressor 15 collects any liquid refrigerant leaving the evaporator. The header tube 19 is typically the coldest point in the refrigeration system because of the presence of liquid refrigerant at low pressure capable of absorbing heat of vaporization. The air translating device 18 includes a conventional motor 20 for driving a blo-wer 21 and a fan 22. The blower 21 effects a circulation of refrigerated air to the respective compartments 12 and 13 through a duct 23. The evaporator 17 and header 19 are disposed in a chamber 24 defined by a wall means 25. As best seen in FIGURES 2 and 5, air is returned from compartment 12 through a duct 26 to chamber 24, and air is returned from compartment 13 through a duct 27 to chamber 24. The blower 21 is disposed in a suitable shroud 28 communicating with the chamber 24 through an opening 29 in a side wall 30 of the Wall means 25 and with the duct 23 through an opening 31. The wall means 25, as shown in FIGURES 3 and 5, further includes a rear wall 32, a top wall 33, a right side wall 34, and a bottom wall 35, said side wall 30, side wall 34, top wall 33 and bottom wall 35 cooperatively defining a front opening 36 which may be removably closed by an insulating closure 37 (as shown in FIGURE 3).

As shown in FIGURE 2, the return ducts 26 and 27 communicate with the chamber 24 in the upper rear portion thereof immediately below top wall 33. The chamber 24 is divided into an upper inlet portion 38 and a lower outlet portion 39 by a heater panel 49 effectively defining a horizontal partition wall means. As shown in FIGURE 2, the front edge 41 of the heater panel 4t) is spaced rearwardly of the closure 37 to define a passage i2 at the front of the chamber 2d for conducting air from the upper portion 38 to the lower portion 39 of the chamber 24. The header 19 in which liquid refrigerant is collected is disposed in the upper chamber portion 38 above the heater panel 40, and the evaporator 17 is disposed in the lower Chamber portion 39 below the heater panel 40.

A wall member 43 depends from the top wall 33 to subdivide the upper inlet chamber portion 38 into a lefthand section 44 and a right-hand section 45. Duct 27 communicates with the chamber section 44, and duct 26 communicates with the chamber section 45. Thus, the return air is maintained in separate streams, in flowing through the upper chamber portion 38 until reaching the front edge 41 of the heater panel il where the streams may commingle and pass together through the lower chamber portion 39 in heat transfer association with the evaporator 17. The relatively moist air in the above freezing compartment 12 flowing past the header i9 is effectively dried thereby before mixing with the colder drier air from the freezer compartment 13, thus effectively facilitating the frost-free operation of the apparatus in reducing frost collection on the evaporator. The relatively smooth wall surfaces defining the chamber portion 3S provide for facilitated subsequent defrosting as will be brought out more fully hereinafter.

As shown in FIGURE 5, the heater panel 4d comprises a fiat panel which may be formed of suitable material such as glass having a suitable electrical heater 46 embedded therein and arranged to be Connected to a suitable electrical power source (not shown). The heater panel di) may be removably installed in the apparatus liti by means of a pair of opposed U-channels 47 mounted on the side walls 30 and 34 of the chamber wall 25 permitting the panel to be slid into place across the chamber 24, as shown in FIG- URE 4. As best seen in FIGURE 5, the electrical heater 46 is provided with closely spaced portions or turns 48 in the right-hand portion of the panel confronting the chamber section 4S under the header 19 for concentrated heat delivery to chamber section 45 for facilitated defrosting thereof. The heater panel 4S may be energized by suitable control means (not shown) to provide heat energy to both the subjacent evaporator 17 and the header 19, as well as to the confronting wall surfaces of the wall means and wall 43. As the incoming relatively moist air tends to collect first on the header 19 and adjacent wall surfaces, the relatively large frost deposit on the header and confronting wall surfaces is melted by the concentrated heat delivery thereto by the heater portion 48 which provides the heat energy not only in the form of radiant energy but also by convection. Similarly as best seen in FIGURE 5, both radiant and convection heating of the inlet chamber section 44 is effected by the heater panel 40, although to a somewhat lesser degree because of the wider spacing of heater turns in the left-hand portion of heater 46. The evaporator is concurrently defrosted by the radiant heat energy from panel 40.

Thus, the defrost heater panel #tti serves both as a means for delivering defrost heat energy to the portions of the frost-free refrigeration system on which the frost is collected and as a means for partitioning the evaporator chamber into an inlet and outlet portion with the evaporator being disposed in the outlet portion.

The melt produced in the defrosting operation may be conducted through a discharge tube 49 to a pan 5t) in the apparatus space 14 as shown in FlGURE 4. The fan 22 is arranged to direct the relatively warm air from the condenser 11S and compressor 15 over the pan 59 for evaporation of the collected melt and delivery thereof to the ambient atmosphere.

Servicing of the apparatus l() is extremely simple as the heater panel 40 may be slid outwardly from the channels 47 upon removal of the closure 37 for ready access to the chamber 24. While the invention has been illustrated in connection with a dual compartment apparatus having an upper fresh food compartment 12 and a lower freezer compartment 13, it is obvious that the invention may be similarly employed with other refrigeration apparatuses, such as those having the freezer compartment on top and the fresh food Compartment below, or having solely a freezer compartment or a fresh food compartment. In the apparatuses having only a single compartment, the wall member 43 may be omitted as desired.

While I have shown and described one embodiment of my invention, it is to be understood that it is capable of many modifications. Changes, therefore, in the construction and arrangement may be made without departing from the spirit and scope of the invention as defined in the appended claims.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. Refrigeration apparatus comprising:

means defining an enclosure to be refrigerated;

wall means defining a chamber having an air inlet, and

an air outlet;

air chilling means in said chamber;

means for circulating air from said outlet to said er1- closure means and from said enclosure means to said chamber through said inlet; and

heater means in said chamber for melting frost, said heater means defining partition means dividing said chamber into an inlet portion communicating with said air inlet and an outlet portion communicating with said air outlet for conducting circulated l air from said air inlet seriatim through said inlet and outlet portions to said air outlet.

2. The refrigeration apparatus of claim 1 further including means sub-dividing said inlet portion of the chamber into first and second sections.

3. The refrigeration apparatus of claim 2 wherein said enclosure includes first and `second compartments and said wall means further defines a second inlet, said first named inlet communicating with said rst compartment and said first section of said chamber inlet portion and said second inlet communicating with said second compartment and said second section of said chamber inlet portion, said circulating means further including means for circulating air from said enclosure means to said chamber through said second inlet.

4. The refrigeration apparatus of claim 1 further including means in said inlet portion for drying the air before delivery thereof to said chilling means.

5. The refrigeration apparatus of claim 4 further including means sub-dividing said inlet portion of said chamber into first and second sections, and wherein said enclosure includes first and second compartments and said wall means further defines a second inlet, said first named inlet communicating with said first compartment and said first section of the chamber inlet portion and said second inlet communicating with said second compartment and said second section of the chamber inlet portion, said circulating means further including means for circulating air from said enclosure means to said chamber through said second inlet, said air chilling and circulating means causes said first compartment to be refrigerated to a sub-freezing temperature and said second compartment to be refrigerated to an above-freezing temperature, and said drying means is disposed in said second section of the chamber inlet portion.

6. The refrigeration apparatus of claim 4 further including means sub-dividing said inlet portion of the chamber into first and second sections and said drying means is disposed in only one of said sections.

7. The refrigeration apparatus of claim 4 wherein said heater means is arranged to provide high heat delivery to adjacent said drying means.

S. The refrigeration apparatus of claim 1 wherein said air chilling means is disposed in said outlet portion of the chamber.

9. The refrigeration apparatus of claim 1 wherein said chilling means includes an evaporator and header means associated with said evaporator for collecting liquid refrigerant, said header means being positioned in said inlet portion of said chamber and said evaporator being positioned in said outlet portion of said chamber whereby the circulated air passes in heat transfer association seriatim with said header means and said evaporator and is dried by said header means prior to passing said evaporator.

10. The refrigeration apparatus of claim 1 wherein said partition means comprises a substantially llat panel extending horizontally across said chamber forwardly from said air inlet and having a forward edge spaced from said chamber wall means to define a flow passage between said inlet and outlet portions of the chamber.

11. The refrigeration apparatus of claim 1 including means for removably supporting said heater means.

12. The refrigeration apparatus of claim 1 wherein said heater means provides heat to each of said chamber portions.y

References Cited UNITED STATES PATENTS WILLIAM J. WYE, Primary Examiner. 

